In this project, we propose a new detection technology for identification of oligonucleotides, which works by detecting a bio-electronic response from hybridized duplexes. Compared with the conventional approach of using dye tagged oligos, the proposed electrochemical detector has significant advantages. Electrochemical sensing can be implemented using relatively simple equipment. Analysis can be performed in solution. In the proposed approach, no tagging of target molecules is required. When fully developed, highly integrated electronic chips, previously developed for imaging applications, can be modified and can be used as a new generation of inexpensive, disposable, electrochemical DNA microarray sensors.